#include <bits/stdc++.h> #include <ext/pb_ds/assoc_container.hpp> #include <ext/pb_ds/tree_policy.hpp> #define mp make_pair #define pb push_back #define ppb pop_back #define pf push_front #define ppf pop_front #define eb emplace_back #define st first #define nd second #define vt vector #define VAR(__var) #__var << ": " << __var << " " #define PAIR(__var) #__var << ": " << __var.first << ", " << __var.second << " " #define FOR(__var, __start, __end) for(long long __var=__start; __var<__end; ++__var) #define FORB(__var, __start, __end) for(int __var=__start; __var>__end; --__var) #define REP(__var, __cnt) for(int __var=0; __var<(__cnt); ++__var) #define EACH(__var, __x) for(auto __var : __x) #define maxi(__x, __y) __x = (__x>__y?__x:__y) #define mini(__x, __y) __x = (__x<__y?__x:__y) #define all(__var) (__var).begin(),(__var).end() #define rall(__var) (__var).rbegin(),(__var).rend() #define sz(__var) (int)(__var).size() using namespace std; using namespace __gnu_pbds; template <typename T> using ord_set = tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>; #ifdef DEBUG template<typename Stream, typename T1, typename T2> Stream& operator << (Stream& out, pair<T1, T2> a) {return out << "(" << a.st << ", " << a.nd << ")";} template<typename Stream, typename T> Stream &operator << (Stream& out, T v) { out << "{"; int i = 0; for (auto x : v) out << x << ((++ i) != sz(v) ? ", " : ""); return out << "}"; } template<typename... Args> void dump(Args... x) {((cerr << x << ", "), ...) << '\n';} #define debug(x...) cerr << "[" #x "]: ", dump(x) #else #define debug(...) 0 #endif typedef long long ll; typedef long double ld; typedef pair<ll, ll> pll; typedef pair<int, int> pii; const bool __test_cases = false; const int INF = 1e9+2137; void solve() { ll n; cin >> n; vt<ll> pref(n+1, 0); gp_hash_table<ll, ll> cnt; FOR(i, 1, n+1) pref[i] = 2ll*i-1ll+pref[i-1]; FOR(i, 1, n+1) FOR(j, i, n+1) { ll s = i*i+j*j; if(s <= n*n) ++cnt[s]; } ll res = 0; FOR(i, 2, n+1) { FOR(j, i, n+1) { ll sum = pref[j]-pref[i-1]; if(cnt.find(sum) == cnt.end()) continue; res += cnt[sum]; } } cout << res << '\n'; } int32_t main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); int t=1; if(__test_cases) cin >> t; while(t--) { solve(); } return 0; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 | #include <bits/stdc++.h> #include <ext/pb_ds/assoc_container.hpp> #include <ext/pb_ds/tree_policy.hpp> #define mp make_pair #define pb push_back #define ppb pop_back #define pf push_front #define ppf pop_front #define eb emplace_back #define st first #define nd second #define vt vector #define VAR(__var) #__var << ": " << __var << " " #define PAIR(__var) #__var << ": " << __var.first << ", " << __var.second << " " #define FOR(__var, __start, __end) for(long long __var=__start; __var<__end; ++__var) #define FORB(__var, __start, __end) for(int __var=__start; __var>__end; --__var) #define REP(__var, __cnt) for(int __var=0; __var<(__cnt); ++__var) #define EACH(__var, __x) for(auto __var : __x) #define maxi(__x, __y) __x = (__x>__y?__x:__y) #define mini(__x, __y) __x = (__x<__y?__x:__y) #define all(__var) (__var).begin(),(__var).end() #define rall(__var) (__var).rbegin(),(__var).rend() #define sz(__var) (int)(__var).size() using namespace std; using namespace __gnu_pbds; template <typename T> using ord_set = tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>; #ifdef DEBUG template<typename Stream, typename T1, typename T2> Stream& operator << (Stream& out, pair<T1, T2> a) {return out << "(" << a.st << ", " << a.nd << ")";} template<typename Stream, typename T> Stream &operator << (Stream& out, T v) { out << "{"; int i = 0; for (auto x : v) out << x << ((++ i) != sz(v) ? ", " : ""); return out << "}"; } template<typename... Args> void dump(Args... x) {((cerr << x << ", "), ...) << '\n';} #define debug(x...) cerr << "[" #x "]: ", dump(x) #else #define debug(...) 0 #endif typedef long long ll; typedef long double ld; typedef pair<ll, ll> pll; typedef pair<int, int> pii; const bool __test_cases = false; const int INF = 1e9+2137; void solve() { ll n; cin >> n; vt<ll> pref(n+1, 0); gp_hash_table<ll, ll> cnt; FOR(i, 1, n+1) pref[i] = 2ll*i-1ll+pref[i-1]; FOR(i, 1, n+1) FOR(j, i, n+1) { ll s = i*i+j*j; if(s <= n*n) ++cnt[s]; } ll res = 0; FOR(i, 2, n+1) { FOR(j, i, n+1) { ll sum = pref[j]-pref[i-1]; if(cnt.find(sum) == cnt.end()) continue; res += cnt[sum]; } } cout << res << '\n'; } int32_t main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); int t=1; if(__test_cases) cin >> t; while(t--) { solve(); } return 0; } |